body {
    font-family: Arial, sans-serif;
    background-color: #f8f9fa;
}

.card-hotel {
    border-top: 4px solid #0d6efd;
    transition: all 0.3s ease;
}

.card-hotel:hover {
    box-shadow: 0 .5rem 1rem rgba(0,0,0,.15);
}

.form-control:invalid {
    border-color: #dc3545;
}

.error-tip {
    display: none;
    font-size: 0.875em;
    color: #dc3545;
}